Search

Compare outcomes of Melody valve to mechanical mitral valve replacement (MVR) for young children.Children who underwent Melody MVR from 2014-2020 were case-matched to mechanical MVR patients. Transplant-free survival and cumulative incidence of re-intervention were compared. A sub-analysis was performed for infants1 year of age (n=9 Melody MVRs and their matches).Twelve children underwent Melody MVR. Two (17%) children salvaged from mechanical support died. Five (50%) of 10 survivors had subsequent MVR. At 1 and 3 years, transplant free survival (Melody: 83%, 83%; mechanical: 83%, 67%; p=0.180) and re-intervention (Melody: 9%, 39%; mechanical: 0%, 18% p=0.18) were equivalent between groups. For children1 year of age, Melody MVR had a modest survival benefit (Melody: 89%, 89%; mechanical: 80%, 60%; p=0.046) while rate of re-intervention remained equivalent (Melody: 13%, 32%; mechanical: 0%, 22%; p=0.32).For patients1 year old, Melody MVR offers a promising alternative and is a reasonable bridge to mechanical MVR which can be performed safely at an older age. Further studies are necessary to corroborate these findings.

The optimal management pathway for the dysfunctional right ventricular outflow tract (RVOT) is uncertain. We evaluated the long-term outcomes and clinical impact of stent implantation for obstructed RVOTs in an era of rapidly progressing transcatheter pulmonary valve technology.Retrospective review of 151 children with a biventricular repair who underwent stenting of obstructed RVOT between 1991 and 2017.RVOT stenting resulted in significant changes in peak right ventricle (RV)-to-pulmonary artery (PA) gradient (39.4 ± 17.1-14.9 ± 8.3; p 0.001) and RV-to-aortic pressure ratio (0.78 ± 0.22-0.49 ± 0.13; p 0.001). Subsequent percutaneous reinterventions in 51 children to palliate recurrent stenosis were similarly effective. Ninety-nine (66%) children reached the primary outcome of subsequent pulmonary valve replacement (PVR). Freedom from PVR from the time of stent implantation was 91%, 51%, and 23% at 1, 5, and 10 years, respectively. Small balloon diameters for stent deployment were associated with shorter freedom from PVR. When additional children without stent palliation (with RV-to-PA conduits) were added to the stent cohort (total 506 children), the multistate analysis showed the longest freedom from PVR in those with stent palliation and subsequent catheter reintervention. Pulmonary regurgitation was well-tolerated clinically. Indexed RV dimensions and function estimated by echocardiography remained stable at last follow up or before primary outcome.Prolongation of conduit longevity with stent implant remains an important strategy to allow for somatic growth to optimize the risk-benefit profile for subsequent surgical or transcatheter pulmonary valve replacement performed at an older age.

The parallel conductance volume, created by the conductivity of structures surrounding the ventricular blood pool, can be estimated by using a saline dilution technique. This paper examines the use of a novel volume reduction method, during a standard vena caval preload reduction maneuver, as an alternative to the routinely used saline dilution method to calibrate conductance catheter measurements in the left (LV) and right ventricle (RV) of animals and humans. The serial reproducibility of both methods was examined by measurement of percent difference, and by assessing the coefficient of repeatability 1) between two measurements within the same subject, 2) between the two techniques, and 3) interobserver variability. The effect of ventricular size and contractile state on the volume reduction technique was also observed. It was essential to ensure the technique was not affected by inotropic state. The volume reduction technique and saline dilution method were repeated at three different loading states (baseline, 5, and 10 μg · kg−1 · min−1 of dobutamine). The coefficient of repeatability between serial measurements was similar for both the volume reduction and saline dilution methods, and good interobserver variability was demonstrated. The volume reduction technique was compared with the saline dilution technique over a large range of ventricular sizes. No significant difference was observed in the RV or LV of adult humans or in the LV of neonatal pigs and children. There was no significant effect on either the saline dilution or the volume reduction technique as the inotropic state increased. In conclusion, the volume reduction technique is neither affected by ventricular size nor contractile state, is repeatable between different observers, and can be used to substitute the saline dilution method when preload reduction of the ventricle is being employed.